1. Field of the Invention
The present invention relates to a light emitting device package structure and a method for fabricating thereof, and more particularly, relates to a light emitting device package structure with a small size and low heat resistance and a method for fabricating thereof.
2. Description of the Related Art
Light emitting diodes (LEDs) have low volume, good luminance efficiency and fast operating speed and as such, play an important role in many applications including illumination devices or display products. LEDs, initially, have been applied in cellular phones and small sized devices such as remote controllers. With advanced development of high powered and high brightness LEDs, LEDs are now being applied in automobiles, illumination devices and large outdoor display products. However, along with high power and high brightness for LEDs, especially for backlight and electronic illumination applications, heat increases and heat dissipation becomes more of a problem. The conventional wire-bonding type LED package structure has poor heat dissipating efficiency. Thus, a high power and high brightness LED, packaged with the conventional wire-bonding type LED package structure, may not be able to dissipate heat effectively, resulting in an increased operating temperature. Therefore, it this example, the conventional LED package structure is non-durable, deteriorates relatively quickly and has a relatively short lifespan.
FIG. 1 shows a conventional light emitting diode package structure 100, wherein an LED chip 31 is connected to a silicon sub-mount chip 30 by a soldering process or by a thermal pad using a bonding process. The LED chip 31 is electrically connected to a leadframe 34 by a golden wire 32 using a wire binding process. The silicon sub-mount chip 30 is connected to an underlying heat-sinking slug 37. A silicon sealing glue 36 is used to fix the LED chip 31. A lens 35 is disposed on the silicon sealing glue 36. A plastic case 38 is combined with the leadframe 34, the heat-sinking slug 37 and the silicon sealing glue 36 to form a package structure. Therefore, due to the fabrication process, the throughput can not be improved. Specifically, when an LED of the conventional LED package structure is arranged in a pixel array for illumination or display, pitch between each LED can not be scaled down due to the large leadframe and plastic case area. Therefore, pixel continuity and visual effect is hindered.
As such, a novel light emitting device package structure with smaller size and lower heat resistance than the conventional LED package structure and a method for fabricating thereof are desirable.